package com.luke.boot.spring_security.util;

import java.security.MessageDigest;

/**
 * MD5 工具类-建议添油加醋的对入参 str 改造一下
 * 
 * @author Administrator
 *
 */
public class MD5Util {

	// 工具类不允许被实例化
	private MD5Util() throws Exception {
		throw new Exception("异常");
	}

	public static String encode(String str) {
		MessageDigest md5 = null;
		try {
			md5 = MessageDigest.getInstance("MD5");
		} catch (Exception e) {
			throw new RuntimeException(e);
		}
		char[] charArray = str.toCharArray();
		byte[] byteArray = new byte[charArray.length];

		for (int i = 0; i < charArray.length; i++)
			byteArray[i] = (byte) charArray[i];
		byte[] md5Bytes = md5.digest(byteArray);
		StringBuffer hexValue = new StringBuffer();
		for (int i = 0; i < md5Bytes.length; i++) {
			int val = ((int) md5Bytes[i]) & 0xff;
			if (val < 16) {
				hexValue.append("0");
			}

			hexValue.append(Integer.toHexString(val));
		}
		return hexValue.toString();
	}

	public static void main(String[] args) {
		//System.out.println(encode("yyyuuu"));
		System.out.println(encode("123"));
		System.out.println(encode("456"));
	}
}
